1. Field
This invention relates to rifles and particularly to systems for increasing the accuracy of rifles. It is particularly directed to systems including weight devices affixed to the muzzle end of rifle barrels to dampen vibration resulting from the firing of bullets through such barrels. It is also directed to muzzle brakes attached to rifle muzzles to channel discharged propulsion gases in directions other than axially as the slug from a fired bullet travels the length of the barrel.
2. State of the Art
There has long been a desire among marksmen for firearms to be as accurate and consistent as possible during firing. This desire is particularly characteristic of marksmen who engage in rifle target shooting competitions. Consequently, considerable effort has .Iadd.been .Iaddend.to eliminate or at least minimize those factors that adversely affect accurate shooting. It is well recognized that two of the factors adversely affecting accurate rifle marksmanship are (1) the barrel vibration which inevitably occurs upon firing of the weapon and (2) the recoil to which the marksman is subjected upon firing. Attempts to eliminate such barrel vibration and recoil have involved the use of various types and kinds of bedding materials as shock absorbers and dampeners between the barrel and the action assemblies and stocks of a rifle. The kinds and positioning of mounting screws associated with the components of a rifle have been the subject of design scrutiny. Different stock and barrel configurations have been tried. Nevertheless, inconsistent paths of trajectory of ballistic slugs discharged from their muzzles remain inherently characteristic of rifles. .[.These inconsistencies are particularly objectionable with the firing of certain factory loaded cartridges, due to the vibrations of the barrels which are inevitably set in motion upon discharge of a firearm which is not designed specifically for use with that cartridge..].
It has been recognized that, in some cases, it is possible to "match" a particular rifle with a particular cartridge to minimize barrel vibration, thereby to increase accuracy. To "match" a cartridge with a particular rifle, it may be necessary to vary .[.slug.]. .Iadd.bullet .Iaddend.weight .Iadd.or type.Iaddend., the type .[.and.]. .Iadd.or .Iaddend.amount of powder used, or other factors.[., such as the center of gravity of the rifle.].. A best match of ammunition will result in the exiting of a .[.slug.]. .Iadd.bullet .Iaddend.from the barrel muzzle at or as near as possible to .[.the peak.]. .Iadd.a anti-node (i.e., peaks and valleys that correspond to minimum barrel velocity.Iaddend.) of the vibration curve .[.for the.]. .Iadd.representative of transverse .Iaddend.barrel vibrations induced by the firing of the rifle. When the exit of the bullet is at a .[.peak.]. .Iadd.node .Iaddend.of the vibration curve .Iadd.as plotted against time.Iaddend., minimal bullet path deflection occurs (.Iadd.see FIG. 8.Iaddend.).
Weights have been heretofore attached to the muzzle ends of rifle barrels as a means of dampening barrel vibrations set in motion by discharge of the firearm. U.S. Pat. No. 4,726,280, for example, discloses mounting a muzzle member.[., which serves as a counterweight.]. on the muzzle end of a gun barrel. .Iadd.Although not stated in U.S. Pat. No. 4,726,280, it is generally understood that such a muzzle member may serve as a counterweight. .Iaddend.The muzzle member is threaded onto the barrel, and is locked in place. Anschutz and Co. G.M.B., through the 1989 catalog of its distributor, Precision sales International, Inc of Westfield, Mass., discloses, at pages 11 and 16, barrel extensions for rifles that include removable weights. .[.Interchanging these weights enables a marksman to vary selectively the amount of weight used for dampening purposes..]. .Iadd.Although not stated in the 1989 catalog of Anschutz and Co. G.M.B., it is understood that interchanging such weights may enable a marksman to vary selectively the amount of weight used for damping purposes. .Iaddend.
Muzzle brakes have also been used in the past with rifles. The known muzzle brakes function to exhaust propulsion gases as a means of reducing recoil and of dissipating propulsion gases in a direction or directions other than out the muzzle of the barrel. The muzzle brakes heretofore known characteristically cause a noticeable increase in noise and concussion to the marksman. The known muzzle brakes have been attached to the muzzle end or a rifle barrel, and thus inherently add a dampening weight.